Alertmanger stopped working with smtp-relay.gmail.com smarthost

[Moritz Tanzer]

Hi all!

I've been using the smtp-relay.gmail.com smarthost without authentictaion but it stopped working.
But I can send mails via local postfix using the gmail relay host, so the issue seems to be on the Alertmanager side.


Alertmanger log file:
receiver=email integration=email[0] msg="Notify attempt failed, will retry later" attempts=1 err="send EHLO command: EOF"
msg="Notify for alerts failed" num_alerts=1 err="email/email[0]: notify retry canceled after 6 attempts: send EHLO command: EOF"

My Alertmanager config:

global:
  smtp_smarthost: smtp-relay.gmail.com:587
  smtp_from: 'Alertmanager <alertmanager@XXX>'
  smtp_require_tls: true

route:
  group_by: ['alertname']
  group_wait: 10s
  group_interval: 10s
  repeat_interval: 24h
  receiver: 'email'


receivers:
  - name: 'email'
    email_configs:
    - to: 'XXX'
      send_resolved: true

    
Thanks in advance!

[Brian Candler]

Alertmanager version?

Try logging into the same host where alertmanager runs, and running the following:

openssl s_client -connect smtp-relay.gmail.com:587 -starttls smtp

ehlo mydomain.com

mail from:<alertm...@mydomain.com>

See if you get an error like this:

550-5.7.0 Mail relay denied [<address>]. Invalid credentials for

550-5.7.0 relay for one of the domains in: mydomain.com (as obtained from HELO and

550-5.7.0 MAIL FROM).

550-5.7.0 Email is being sent from a domain or IP address which isn't registered

550-5.7.0 in your G Suite account. Please login to your G Suite account and

550-5.7.0 verify that your sending device IP address has been registered within

550-5.7.0 the G Suite SMTP Relay Settings. For more information, please visit

550 5.7.0  https://support.google.com/a/answer/6140680#maildenied

One possibility is that your host has gained a new external IP address (on IPv6 perhaps?) which has not been registered.

[Moritz Tanzer]

Thanks for your reply!

I tried it with version 0.19.0, 0.20.0 and 0.21.0

IP address is 100% correct configured in the Gsuite relay settings.

I can connect from command line as you mentioned and I can send mails from this host with local postfix using smtp-relay.gmail.com as relayhost.

[Sandeep Rao Kokkirala]

Try to login into Alertmanager pod and try if your able to resolve DNS from alertmanager pod?

[Moritz Tanzer]

Thanks for your input! DNS resolution works as expected.